In Thursday’s mail, there it was: a bright red envelope with a British stamp, addressed to you. Inside was a birthday card from your doting Gaga, wishing you a most wonderful fifth birthday. The two crisp bills in the envelope didn’t hold your attention nearly as much as the fact that the card came with a pin with a big red “5” on it. You turned it over and over in your fingers, and wondered out loud if you should wear it right now.

“I don’t know,” I said. “You’re still Four, aren’t you? If you wear your ‘5’ pin right now, Four might feel bad. Maybe you should wait a few days. Maybe you shouldn’t wear it until your birthday party.”

I expected you to tell me in no uncertain terms that you wanted to wear the pin anyway, that it was yours and that you could do with it what you liked. I expected you to say something to the effect of, “I’m in charge of me. I make my own rules.” But you took me seriously, calmly even, putting the pin aside until the weekend, when you were surrounded by a frenetic gaggle of senior kindergarten classmates at a bowling alley.

Yes, we ushered out four and rang in five by taking 10 four- and five-year-olds bowling on Saturday morning. And, let me tell you, it was a good call. The idea of your birthday party had overwhelmed me for weeks. Every time I thought about what to do, I got tired: the food, the invitations, the guest list, the decisions, the cleaning, the entertainment. The guilt at the possibility of not getting everything exactly right. Not to mention fitting it all into a weekend filled with grandparental visits and out-of-town guests, a children’s event at the synagogue, and, oh, a book launch. Picking up the phone and calling Mario’s Bowl was the most liberating thing I’ve done in months: all we had to do was invite the kids and bring a cake. And loot bags. With the surge of energy I got from the weight of birthday-party planning lifted from my shoulders, I managed to get it together to get out my mother’s — your Bubbie Ruthi’s — vintage Betty Crocker cookbook (“Decorating fancy cakes has become a fascinating hobby for many women. With a little practice... you too can turn out pretty decorations for special occasion cakes. And someday, you will perhaps trim a tiered wedding cake for a daughter or friend.”) and whip up — with the help of you and your brother — a Smartie-dotted rendition of Black Midnight Cake:

Your brother in particular found it fascinating. Yes he did.

Yes, outsourcing the birthday party was the best thing in the world we could have done, even if only because, at the end of an hour of bowling with you and your friends and a few toddlers thrown in for good measure, and then helping corral pizza and cake and loot bags, I was so exhausted that my jaw ached and I had to stare at the ceiling for half an hour in bed and thank God that we had chosen not to hold the event at our house because then I would have been catatonic.

It’s not that anyone behaved badly. In fact, you were all models of picture-perfect SK behaviour. It’s just, Rowan, that you — like all of your friends — are the merest bit, well, exhausting. I’ll tell you a secret: Four (also known as your fifth year on this earth) has tested my resources so often that sometimes I felt like I didn’t have thumbs, like I’ve been holding on with only an imperfect, slightly treacherous grip. Even though I jokingly told you that you might not want to cut off your time as a four-year-old any earlier than you have to, during the past 365 days, part of me has often wished for the end of Four, for the arrival of Five and, perhaps, a slightly more peaceful time. Some days, Five couldn’t arrive soon enough.

Don’t get me wrong: Four has also been fantastic, fabulous. All vestiges of babyhood have fallen away from you over the past year, replaced by big-kid confidence. You still love to be read to, but now you read to us, too, entire books from cover to cover with barely a stumble. You tolerate Thomas the Tank Engine and Elmo, but you have started to cross the line into Pokémon and Bakugans and — when we let you — computer games. Big-kid stuff. You have friends, real friends, with whom you create complex games and worlds during the courtyard recess. You are competent, insisting on carrying in the bags of groceries, programming the stereo, addressing the birthday invitations. You probably know more about my iPod than I do, and you take decent photographs. You have real conversations on the telephone, even if you can’t sit still while talking (or, for that matter, while eating) and instead circle the ground floor, climbing up and over the couch and across the radiators as you talk to your Rob, your grandparents, your godparents, your friends, and every single person who calls our house when you’re home, because you won’t let us answer the phone — that’s YOUR job. “I’ll get it!” you yell, jumping up from whatever task is at hand and running for the phone. “I’ll get it!”

Over the past year, I have talked to the parents of many of your friends. Often, I asked them, “So, how’s Four treating you?” And, so often, they roll their eyes and then they hold up their hands and show me that they too have no thumbs, just scabs to show that they once had a grip. And this has, paradoxically, helped to keep me sane.

At the same time, the four-letter parts of Four seem to be fading just a bit, replaced more and more often by the fabulous parts. I’ll tell you another secret: as much as Four was about you learning some of the rules of appropriate behaviour, just as much of it was about me and your other mother learning, again and again, what it means to be a parent, what it means, paradoxically again, to find your equilibrium by embracing the loss of control.

So when you and your nine friends and some of their siblings and your own brother, plus almost that many adults, all showed up at the bowlerama on Saturday, I watched you roll gutter ball after gutter ball and all do your crazy Four- and Five-year-old things: climb all over the ball-return equipment until the bowling alley employees had to tell you to stop; hoard the pink balls; obsess over turn-taking and the correct spelling of everyone’s names on the computers; lie on the floor, spinning a ball and chanting, “It’s the universe! The universe!” You barely ate your pizza, you picked off the pepperoni, you all wanted pink Smarties, you sang alternate, scatological lyrics to Happy Birthday. You were fantastic.

Happy fifth birthday, Rowan. I can’t wait to see what your sixth year brings us.